Which lambda sensor is number 2?

[Stacky]

Hi everyone, i have recently been having troubles with my engine light turning on and off. I took my 2004 156 to have a diagnostics test and it all came back pointing to lambda sensor 2. Have taken them all out and given them a good clean, but my engine light has come on again. Could someone please tell me which one is number 2? Also where is a good place to buy the sensors, and why are they so dear? Anyone found a place that does cheap ones? Thanks

[colcol]

The Lambda sensor number 2 is the dirty one thats tripping the warning message, if you replace the number 2.....then #1+#3+#4 are on the way out, so just do the lot of them, as they will all start tripping the warning.
Replacing them all will give you better fuel economy and lengthen the life of your catalytic convertors.
I did the four in my JTS around about 100k, after it was stumbling and giving 'Go to Dealer' messages.
I have seen some cheaper generics sensors, and some of them have bare wires coming out of them, so you have to crimp your wires onto the cheap generic sensors.
Try Italian Automotive Spares in Melbourne or do a google search, Colin.

[Stacky]

Thanks Colin. i was hoping to just get away with replacing 1 for now as i was told it will cost me $800 for the 4 sensors (without fitting). I cannot afford that right now. Will have to surf the internet and see what i can find. Are they all the same or is each individual one different?

[colcol]

They all seem the same, but thats just a quick look, but most defiantly, the wiring plugs are different, so you can't connect the wrong one up, so that the computer reads number one, when its actually reading number two.
You will need a ring spanner with a split in it, similar to pipe spanner, i think it is 22mm, but check anyway, you will need a long ring spanner, with a split, to loosen the sensor off, and a dwarf*, [short] ring spanner, ring spanner with a split in it, as the working space is limited.
*dwarf spanner is the actual description of the spanner in the tool catalogue, so all you height challeged people don't get upset!, Colin.

[colcol]

The 22mm ring spanners that you have to split on the end of the ring spanner, is best done by using an angle grinder, just make the slot wide enough for the wire to go through, i did purchase a 'lambda socket removal kit' off ebay in the UK, but it didn't work half as good as the 'mongrolled up' 22mm ring spanners, don't buy good expensive Sidchrome or Kincrome spanners, i used well priced and good quality Total Tools, 'tools for trade', worked a treat, Colin.

[Stacky]

Thanks again colcol. So i have to buy 4 individual ones, i can,t just buy 4 of the same one? Thanks for the tip with the spanner. will definately look into that.

[colcol]

If i remember rightly???, there are 2 at the top that are the same and the 2 at the bottom are the same, but different to the top ones, the lengths of the wires and wiring plugs are arranged, so that you can't plug them into the wrong wiring loom.
If you do it yourself, give the old installed lambda sensors a good spray with WD 40 and let them soak overnight, before attempting to remove them as they have been in the hot rusty part of the car for 10 years, Colin.

[Davidm1600]

Col's quite correct re the difference between top and bottom lambda sensors.  Also they do vary in price between which ones you need. 

I can't speak re cost or experience with Australia suppliers for them.  But in replacing all 4 over a period of time on my '03 JTS Sportwagon, I bought them all through EB Spares in the UK.  They have a good website and are easy to deal with, promptly delivered, literally in less than a week and the cost to my mind perfectly reasonable.  From memory, the cost would probably add up to for all 4 sensors to around $800 but its inevitable they will need replacing on the JTS engine.

I have used EB Spares for replacing also the top and bottom front control arms, drop links, Bilstein B4s all around, timing belts, water pump etc etc. 

I know there are some other suppliers in the UK as well as in Aus but I am happy with the service received by them.  Oh and for peace of mind delivery is tracked all the way, the postage cost is also not so bad as one might have thought otherwise.

[colcol]

Just to confirm that the JTS Lambda sensors require a 22mm socket/ring spanner.
Sometimes the scanner will tell you bank number one and bank number two, thats for vee or boxer engines, number one bank will be for the bank containing the number one cylinder, thats the cylinder closest to the front timing case and bank number two will be for the number two cylinder, the other side.
For a four cylinder in line engine, bank number one will be for cylinders number one and two and bank number two will be for cylinders three and four.
Lambda sensor number one, is usually the top Lambda and sensor number two is usually the bottom Lambda.
Replace the four after about 100k, to avoid any dramas, Colin.

[Stacky]

Thanks for the info guys. These are the fault codes I got.

PO430 - catalyser 2, above top limit, intermittent.

PO159 - Lambda 2 signal below catal (slow) No signal, intermittent.

PO156 - Lambda 2 signal catal no signal, intermittent.

P1161 - Preheating resistance 2 below catal. Signal not valid, intermittent.

P1151 - Lambda 2 signal upstream (plausibility) no signal.

PO115 - Water temp sensor, signal not valid/below bottom limit, intermittent.

HUH? Lol.

[colcol]

I would replace all the Lambda Senders, as they all wear out about the same time, replace one and a week later another one will fail.
Take the water temperature sender out and give the body and tail a good clean along with the terminal, sometimes you get corrosion on the senders tail, [thats the long bit that sits in the coolant stream], and it can't read the water temperature, and where it screws in with the thread, make sure it has a good earth, Colin.